//创建一个符号, 一个全新的数据类型

const syb1 = Symbol();
const syb2 = Symbol("abc");

console.log([syb1, syb2]);
console.log(syb1, syb2);

const syb3 = Symbol('符号1');
const syb4 = Symbol('符号1');

console.log(syb3, syb4, syb3 == syb4);

const symbol1 = Symbol();
const arr = [symbol1];
console.log(arr[0] == symbol1);

console.log([Symbol]);
